Realisation of multi-mode reflector lasers for integrated photonics

The epitaxial growth of III-V materials on silicon is an alternative approach to combining silicon photonics with the active laser source. Substantial progress has been made to reduce the defects created at the III-V / Si interface to a level that has a negligible impact on laser operating current and lifetime, providing quantum dot gain materials are utilized [1], [2]. A number of issues remain for the integration of III-V structures with silicon, not least that of reducing the footprint and ensuring the fabrication required is as simple as possible. While the laser reflectors can be fabricated in the silicon here we focus on using the III-V material, which removes the need to have the III-V / Silicon interface and its associated losses within the laser cavity

InAs quantum dot-based one- and two-port multimode interference reflectors for integrated photonic devices: design, fabrication, and evaluation

1-port and 2-port multi-mode interference reflectors (MMIR) are excellent components for Photonic Integrated Circuits, being highly reflective and easy to fabricate. We demonstrate InAs-Quantum-Dot MMIR lasers, where the high reflectivity is particularly advantageous, with lower threshold current than Fabry-Perot ridge lasers with the same cavity length e.g. 6mA compared to 46-mA. The threshold current density of the 1-mm MMIR laser is equivalent to the Fabry-Perot laser with a 3-mm cavity length. MMIRs have a higher optical slope efficiency, indicating mirror reflectivity above 85%